1. Field of the Invention
The present invention relates to an explosive powder-charge operated setting tool including a first part provided with a cartridge socket, an opposite second part having a mating surface which partially covers an axial projection surface of the cartridge socket, a circular cut-out provided adjacent to the first part, and at least one connection channel, and an annular sealing member located in the circular cut-out of the second part, with the sealing member being supported on the first part outside of the cartridge socket, and with the at least one connection channel extending from the cartridge socket up to a working surface of the sealing member facing in a direction opposite to the setting direction.
2. Description of the Prior Art
International application WO96/39281 discloses an explosive powder charge-operated setting tool having a guide cylinder with an inner bore in which a drive piston is displaceably arranged. A breech block, which is arranged coaxially with the guide cylinder, adjoins the guide cylinder at its side facing in a direction opposite to the setting direction. The breech block is provided with a cartridge socket in its region facing in the setting direction. The inner width of the cartridge socket increases toward the free end of the breech block.
The guide cylinder has, in its end region facing in a direction opposite to the setting direction, a circular cut-out in which a sealing member is fixedly arranged. The circular cut-out divides the end region of the guide cylinder, that faces in the direction opposite to the setting direction, in a central cylindrical section and a circular outer section which surrounds the central cylindrical section. The free end of the central cylindrical section forms a mating surface which secures a cartridge in the cartridge socket. The mating surface projects beyond the remaining portion of the end surface in the direction opposite to the setting direction.
Upon ignition or firing of the cartridge, the propellant gas pressure reaches, through the connection channel which connects the cartridge socket with the cut-out, the inner wall of the circular sealing member which has a U-shaped cross-section the opening of which is opened toward the central longitudinal axis of the sealing member. The propellant gas pressure, which is generated upon firing of the cartridge, does not act only in the setting direction in the setting tool disclosed in the above-mentioned International application. Rather, it also acts in two parallel directions opposite to the setting direction, so that the sealing member expands in two opposite directions.
Accordingly, an object of the present invention is to provide an explosive powder charge-operated setting tool in which the sealing element reliably seals the cartridge-receiving chamber and is pressed toward the first part with a bearing pressure corresponding to the propellant gas pressure.